1. Field of the Invention
This invention relates to a method of rewriting data in an EEPROM (electrically erasable programmable read-only memory), as well as to an EEPROM card.
2. Description of the Related Art
Memory cards of the type incorporating an S-RAM (static random-access memory) inside a case are disadvantageous in that battery back-up is required and the unit price per bit is high. Accordingly, the development of memory cards equipped with an EEPROM designed to eliminate these drawbacks is proceeding. Though a memory card having an internal EEPROM is advantageous in that battery back-up is unnecessary while the unit price per bit is low, the number of rewriting operations possible is on the order 10,000. In terms of reliability, therefore, a memory card of this type is inferior to the card having the internal S-RAM.